Everett , Washington -LRB- CNN -RRB- -- Sprawled out before us sits the exterior of the world 's biggest building by volume . They make airliners here . Big ones .

`` Let 's go see some airplanes ! '' says our Boeing VIP tour guide .

I remind myself : This does n't happen very often .

Yeah yeah yeah , Boeing offers public tours of this 98.3-acre airliner factory north of Seattle every day . This ai n't that . This is special .

As part of a convention of aviation fans called Aviation Geek Fest , we 're gaining ultra-exclusive access to the factory FLOOR . The public tour is limited to the balcony . We 're about to walk knee-deep where Boeing gives birth to some of the world 's biggest and most advanced airliners , including the 747-8 Intercontinental , the 777 Worldliner and the 787 Dreamliner .

Hot damn .

But not so fast -- before we go inside , Boeing has laid down some rules : no photos , no video , for our eyes only .

Here 's a painful development : Our smartphones have been confiscated . Gulp . I 'm already suffering from phantom phone pangs .

We enter through a small , inconspicuous door marked S-1 . Suddenly , we 're surrounded by partly assembled airliners in a room so big it takes on the feeling of an entire world . In some spots , we gaze across an unobstructed view measuring a quarter-mile .

This building is so flippin ' big that -- years ago -- it created its own inside weather patterns , including vapor clouds . They eliminated that by installing a special ventilation system . Today 's factory forecast : avgeeking , with continued avgeeking and a favorable chance of avgeeking later in the day .

Here are a few cool tidbits :

Jaw-dropping perspective

The thrill of being so close to the planes literally stops you in your tracks . Seemingly everywhere you look there 's another five - or six-story-tall airplane towering over you . Some are covered with a green , protective temporary coating . One Dreamliner tail is painted with the familiar British Airways red , white and blue . Another sports New Zealand Air 's cool black-and-white .

Boeing paints the tails before they 're attached to the planes . Then they carefully adjust the tails for balance . Paint adds hundreds of pounds of weight , which would ruin the plane 's balance if the tails were painted after being attached .

Soon these behemoths will jet across vast oceans as they carry travelers to far-flung destinations .

` You 've got ta have secret clearance '

The planes ' huge fuselages are joined together with the help of a giant piece of equipment called a `` saddle . '' This U-shaped metal cage straddles the top of the planes during the body-joining process .

The `` Wing Build '' area -- where workers attach wings to the planes -- is the loudest part of the entire facility . The staccato of rivet guns pierces the heavy air . Whooshing vacuums suck up any dust that may be created when workers drill into the planes ' lightweight carbon composite material .

Security concerns in the plant are real . `` Conversation-restricted area , '' says one sign .

As we walk past a fenced-off zone , our guide quips , `` You 've got ta have secret clearance . I ca n't even go in there ! ''

The rock star engine

Then , like a holy relic brought back from the Crusades -- Boeing lets us touch `` it . ''

By `` it '' we mean the GE90-115B . Guinness calls it the most powerful commercially produced jet engine in the world .

We gather around this rock star engine like thirsty travelers at a desert oasis , each taking turns running our hands across its silver exterior . The lip of the engine 's mouth feels rough , like it has countless scratches etched into it . That design , engineers discovered , helps reduce noise .

This 19,000-pound monster hangs from the wing of a giant 777 , but the engine still looks humongous -- measuring more than 11 feet in diameter . In fact , Boeing says it 's so big you could fit the body of a 737 airliner inside it .

`` There 's no way to sense the sheer size of an airplane without being right there underneath it , '' says NYCAviation.com contributor Ben Granucci , enjoying his first Aviation Geek Fest . Engines like this make it possible for wide-body planes to fly long-distance routes nonstop with only two engines instead of three or four . In fact , the 777 flies many of the world 's longest nonstop routes . In 2005 it set the world distance record for a nonstop commercial airline flight , jetting 13,423 miles from Hong Kong eastbound to London in 22 hours , 22 minutes .

The world 's top flying hauler

Just a few hours earlier , a handful of aviation geeks were hanging out at a hotel next to Paine Field , the airport Boeing uses to test and deliver the factory 's planes .

Then , Granucci tweeted out that the plane that hauls the most cargo by volume in the world just happened to be passing through .

Count me in .

Soon , a dozen camera-wielding geeks are lined up outside the hotel to welcome the Dreamlifter -- a modified 747 -- as it lumbers in for a landing . `` We 're gon na be late for breakfast , '' says avgeek Steve Dillo as he snaps photo after photo . `` But this is worth it . ''

The thing roars like a lion , but it looks like a whale as it slows for touchdown . In the entire world , there are only four of these giant planes . Boeing uses them to ferry big sections of the 787 for final assembly here in Everett . Last year , when a Dreamlifter landed at the wrong airport in Kansas , it was n't exactly a stellar moment .

The Avgeek News Network

This is the fifth avgeek fest , co-sponsored by AirlineReporter.com and Everett 's Future of Flight Museum . The February convention drew a record 300-plus participants from 18 different states and three countries . Former GM and Toyota engineer Philip McKenzie , flew 8,000 miles from Melbourne , Australia , to see how `` things are laid out '' in the factory . Vancouver Airport official Trevor Batstone traveled 100 miles from Canada . Who are these people -- these avgeeks ? What defines them ?

`` It 's someone who always looks up in the sky when they hear a jet roar , '' says Ryan Ewing , 14 , who runs airlinegeeks.com out of his Bethesda , Maryland , home . Ewing was right there in the thick of the geeks with his camera when the Dreamlifter came calling .

The event was born from an aviation-obsessed online community that uses social media to organize and share information . Aviation news sites like Airchive , AirlineReporter , NYCAviation and AirlineGuys all share common friends , connections and interests . When news breaks , their informal social network sometimes challenges traditional news media . This month AirlineReporter and a few other aviation sites broke news about the hijacking of an Ethiopian Airlines 767 in Rome about 30 minutes before many `` legacy '' news organizations , says AirlineReporter founder and editor-in-chief David Parker Brown .

Boeing 's desire to connect with fans and fliers combined with the emerging power of the avgeek nation opened the doors to the exclusive Boeing tours , Brown says . `` Boeing has increasingly realized how smart and educated about aviation avgeeks are . ''

Baby Boeings

The following day southeast of Seattle , Boeing opens up yet another factory for us to tour . This one is the birthplace of what Guinness calls the `` most produced large commercial jet in aviation history '' -- the 737 .

No public tours here . This is a tour for avgeeks and VIPs . `` Avgeeks love getting access to places that are off limits , '' says Brown . `` It 's all about exclusivity . ''

Here 's some 737 tour trivia :

-- This place creates 38 of the planes every month on a moving assembly line . And they 're pushing to increase that rate . `` Even though we joke that the 737 is the ` Baby Boeing , ' it 's still a large and complex machine , '' says Granucci . `` It requires precision to put it together . The fact that you can perform such precise work on a moving target -- I find that to be incredible . ''

-- The facility receives pre-assembled fuselages by train from a factory in Wichita , Kansas .

-- Workers attach wings to the fuselages . It takes about nine hours to put wings on a 737 .

-- The planes also get `` winglets '' -- the tiny , upward pointing wings you see on the wingtips of 737s and other airliners . These doodads reduce drag on the plane and make it more fuel efficient -- by about 4 % .

-- Workers install seats on the planes by using a loading machine they call a `` hay baler . ''

-- In an operation called `` high blow , '' Boeing tests each plane 's passenger cabin for possible leaks during pressurization . The procedure includes putting people inside the planes to listen for leaks .

-- Each 737 is made up of 42 miles of wire and 394,000 separate parts

-- If there 's a problem on the assembly line , workers activate a purple flashing light -- alerting others that they need help . `` Blinking purple is bad for us here , '' says Christian Ofsthus , a Boeing senior manager . `` If there 's something wrong , something does n't fit , we need to do something about that . ''

As the tour ends , we wind through an employee diner named for the World War II symbol Rosie the Riveter , and file back onto our bus . Driving off the property , we spot a train loaded with brand new wingless 737 fuselages headed to the factory behind us .

That triggers spontaneous applause and scattered whoops throughout the bus . Well , you just ca n't get any geekier than that .

`` That is so cool , '' I hear someone say .

`` Yeah , '' said someone else , `` baby planes ! ''

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Boeing allowed aviation fans unique factory access during a February convention

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`` Avgeeks '' toured factories for 737 , 747 , 777 and 787 Dreamliner

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Growing avgeek community challenges legacy news media